Open AccessEntangling two high-Q microwave resonators assisted by a resonator terminated with SQUIDs
Author(s) -
Ming Li,
Ming Hua,
M. Zhang,
FuGuo Deng
Publication year - 2019
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/ab2e1c
Subject(s) - resonator , physics , coupling (piping) , coupling coefficient of resonators , squid , quantum entanglement , microwave , optoelectronics , quantum , quantum mechanics , materials science , ecology , metallurgy , biology
We propose a superconducting circuit for quantum information processing (QIP) on high-quality (high-Q) superconducting resonators (SRs). In the circuit, two high-Q SRs are coupled to a high-frequency SR (acts as a quantum bus) assisted by superconducting quantum interference devices (SQUIDs) terminate in both ends of the high-frequency resonator. Each coupling strength between each high-Q resonator and the high-frequency resonator can be tuned independently from zero to the strong-coupling regime via the external flux threading through the SQUID. In the circuit, the frequencies of the two high-Q resonators are far detuned from the high-frequency resonator. That is, quantum information stored in high-Q resonators cannot be populated in the high-frequency resonator, which lets the bus can be designed to link lots of high-Q resonators for the large-scale QIP. To show the circuit can be used to achieve the QIP, we present a high-fidelity scheme to generate Bell state on the two high-Q resonators. The scheme shows that, to achieve the entanglement operation on high-Q resonators, fast tuning on the coupling is no longer mandatory and the coupling strengths are not required to be turned on or off simultaneously.